WARNING:
This game is not optimized for coop. If you want to play this coop dont get it. You can search online for problems with the coop and will find a long history of many unsolved issues that make the game unplayable for the second player.
Since this was never fixed and instead shadow warrior 3 was released I am giving this a thumbs down.
Now as to why its actually a fun game (in singleplayer):
The game is above all made for one purpose.
Goring endless hordes of enemies to death.
Characters, writing, story etc.. do exist to give context to the slaughter but the sure aren't strong points.
Which they dont need to be.
The game looks really nice even almost ten years later.
Many weapons have the oomph you would expect.
However the game at least on higher difficulties is wanting you to focus in a particular direction.
So you are either slicing everything up or gunning things down with a specific weapon class.
That is still ok since there are a lot of different weapons. Except for the like 20 melee weapons that all do pretty much the same thing for the most part.
What makes melee combat even worse is that enemies can block. Even simple fodder enemies can block you, which isnt the end of the world but it does really hurt the flow of combat if you just stand there for a second.
And you can parry, which you wont, but it does show a bit of a mess in terms of the design decisions.
The worst part is how you get stronger. Every enemy drops random junk with random stat upgrades that are... really miniscule.
So for a useful example you go from 12.5% extra damage to 13% extra damage if you play for a bit.
But most stats arent even that and even more questionable in their use.
But the worst part is: you get thousands of these and one by one put them in the junk pile to sell them.
So you stand there for 10 minutes slowly checking these 1 by 1 to make sure you arent selling something that gives you .1% more damage.
And that isnt even needed. There are so many different weapons. It is completely fine if you reward a weapon for each mission or boss kill when you have so many to choose from. If you make them different enough and fun to play with and frequently hand out new toys, then the slaughter with these new toys is the whole fun of it.
But the game wants repitition. A small selection of pretty big maps with objectives strewn across them again and again and again. The game wants you to play it multiple times on harder and harder difficulties, offering ways to upgrade that would require playing for an absurd amount of hours so that you can get those numbers higher and higher.
If you like it enough that you can play for the sake of playing and grind all those hours doing the same thing again and again then ... sure you might like that. But as it stands I think the game is too long for its own good.
Still at the end of the day what it comes down to is this:
Do you want a game that looks nice where you go in and kill hordes of things brutally and more importantly mindlessly?
Then this is a game for you. Just.... maybe on a sale.